40 mph uphill? Other Armada or Titan TVs?
I’ve been trolling this site for a year. There’s so much info I that haven’t needed to ask a question until now! Tv: 2006 Armada LE 5.6L DOHC V8 with factory tow package. Tow rating 9000lbs. 305...
Forum Discussion
There have been a lot of great posts but I would like to add a little more.
Something I caught in your first post is you bypassed the transmission cooling loop in the radiator when you installed the aux cooler. This is a bad idea. Oil / air heat exchangers (like an aux trans cooler) are not terribly effecient, especially when there is not much airflow over them, like when you are climbing a steep hill or backing into a campsite. Without active cooling the trans fluid heats up in a hurry. The oil / water heat exchanger in the radiator is very efficent and works even if the car is not moving. The coolant in the radiater is a pretty big heat sink and will take a lot of heat from the trans fluid before it starts to get too hot. You really should run the loop in the radiator and the aux cooler in series. I had a 2004 Explorer V8 and towed my 5200lb loaded trailer (similar to your trailer) with it. Explorer was rated for 7000lbs and I was within all specs. It had the radiator loop deleted at the factory and just used a stacked plate air cooler. Twice after towing home fluid overheated and leaked past the front seal while I was backing into my space. It also went into protection mode more than once where shifts were very firm going up slow hills. I would have had to do something if I had kept the Explorer.
I currently have a similar setup to you, my 2007 Expedition EL 5.4 has 300hp and 385ftlbs torque with a 6spd transmission. My experience is same as you describe When towing up significant grades especially at elevation I definately slow down to 40-45 and be in 2nd or maybe 3rd. I do not have tow haul mode, so I often will manualy gear down before the transmission wants to and hold the gear as long as necessary keeping the engine at 4000-4500 rpm. I always lift off the throttle when I shift down. OHC engines make power at higher rpm and are designed to run there. For those who have been around awhile and are used to old big blocks this is the opposite experience. While a big block may be close to blowing up, a OHC engine is just getting warmed up at 4000. Higher rpm will usually keep the torque converter locked, it will also run the water pump faster and if you have an engine powered cooling fan (I do) it will run faster too. It is better to go a few mph slower with the engine rpm up than to go a little faster with the engine rpm lower.
Here in SoCal I have to climb a mountain to go just about anywhere. I have towed over everything from mild to moderate interstate grades, more significant secondary highway grades, and some steep mountain road grades that had me in 1st. I have been satisfied with the Expedition's towing performance and love it for people / stuff hauling the rest of the time I am not towing. Would I love a new ecoboost Expedition? Heck yes, but I am really enjoying NOT having a car payment!
Something I caught in your first post is you bypassed the transmission cooling loop in the radiator when you installed the aux cooler. This is a bad idea. Oil / air heat exchangers (like an aux trans cooler) are not terribly effecient, especially when there is not much airflow over them, like when you are climbing a steep hill or backing into a campsite. Without active cooling the trans fluid heats up in a hurry. The oil / water heat exchanger in the radiator is very efficent and works even if the car is not moving. The coolant in the radiater is a pretty big heat sink and will take a lot of heat from the trans fluid before it starts to get too hot. You really should run the loop in the radiator and the aux cooler in series. I had a 2004 Explorer V8 and towed my 5200lb loaded trailer (similar to your trailer) with it. Explorer was rated for 7000lbs and I was within all specs. It had the radiator loop deleted at the factory and just used a stacked plate air cooler. Twice after towing home fluid overheated and leaked past the front seal while I was backing into my space. It also went into protection mode more than once where shifts were very firm going up slow hills. I would have had to do something if I had kept the Explorer.
I currently have a similar setup to you, my 2007 Expedition EL 5.4 has 300hp and 385ftlbs torque with a 6spd transmission. My experience is same as you describe When towing up significant grades especially at elevation I definately slow down to 40-45 and be in 2nd or maybe 3rd. I do not have tow haul mode, so I often will manualy gear down before the transmission wants to and hold the gear as long as necessary keeping the engine at 4000-4500 rpm. I always lift off the throttle when I shift down. OHC engines make power at higher rpm and are designed to run there. For those who have been around awhile and are used to old big blocks this is the opposite experience. While a big block may be close to blowing up, a OHC engine is just getting warmed up at 4000. Higher rpm will usually keep the torque converter locked, it will also run the water pump faster and if you have an engine powered cooling fan (I do) it will run faster too. It is better to go a few mph slower with the engine rpm up than to go a little faster with the engine rpm lower.
Here in SoCal I have to climb a mountain to go just about anywhere. I have towed over everything from mild to moderate interstate grades, more significant secondary highway grades, and some steep mountain road grades that had me in 1st. I have been satisfied with the Expedition's towing performance and love it for people / stuff hauling the rest of the time I am not towing. Would I love a new ecoboost Expedition? Heck yes, but I am really enjoying NOT having a car payment!
